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19 
20 #pragma once
21 
22 #include <sal/types.h>
23 #include <basegfx/range/b2ibox.hxx>
24 
25 
26 namespace basegfx::utils
27 {
28     namespace RectClipFlags
29     {
30         const sal_uInt32 LEFT   = sal_Int32(0x01);
31         const sal_uInt32 RIGHT  = sal_Int32(0x02);
32         const sal_uInt32 TOP    = sal_Int32(0x04);
33         const sal_uInt32 BOTTOM = sal_Int32(0x08);
34     }
35 
36     /** Calc clip mask for Cohen-Sutherland rectangle clip
37 
38         This function returns a clip mask used for the
39         Cohen-Sutherland rectangle clip method, where one or more
40         of the lower four bits are set, if the given point is
41         outside one or more of the four half planes defining the
42         rectangle (see RectClipFlags for possible values)
43      */
44     template< class Point, class Rect > inline
getCohenSutherlandClipFlags(const Point & rP,const Rect & rR)45        sal_uInt32 getCohenSutherlandClipFlags( const Point& rP,
46                                                const Rect&  rR )
47     {
48         // maxY | minY | maxX | minX
49         sal_uInt32 clip;
50         clip = (rP.getX() < rR.getMinX()) << 0;
51         clip |= (rP.getX() > rR.getMaxX()) << 1;
52         clip |= (rP.getY() < rR.getMinY()) << 2;
53         clip |= (rP.getY() > rR.getMaxY()) << 3;
54         return clip;
55     }
56 
57     /// Cohen-Sutherland mask calculation - overload for boxes.
58     template< class Point > inline
getCohenSutherlandClipFlags(const Point & rP,const B2IBox & rB)59        sal_uInt32 getCohenSutherlandClipFlags( const Point&  rP,
60                                                const B2IBox& rB )
61     {
62         // maxY | minY | maxX | minX
63         sal_uInt32 clip;
64         clip = (rP.getX() <  rB.getMinX()) << 0;
65         clip |= (rP.getX() >= rB.getMaxX()) << 1;
66         clip |= (rP.getY() <  rB.getMinY()) << 2;
67         clip |= (rP.getY() >= rB.getMaxY()) << 3;
68         return clip;
69     }
70 }
71 
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73